Data/hora: 08/06/2024 14:50:01

Biblioteca(s): | Epagri-Sede.
Data corrente: | 08/12/2021
Data da última atualização: | 08/12/2021
Autoria: | RESENDE, R. S.; ARAÚJO, E. R.; KLABUNDE, G. H. F.; ROSSATO, M.
Título: | First report of Pantoea ananatis causing a foliar and bulb disease on onion in Brazil.
Ano de publicação: | 2021
Fonte/Imprenta: | Journal of Plant Pathology, Berlin, v. , n. , p. 1-2, 2021.
Idioma: | Inglês
Conteúdo: | Since 2018, sweet onions (Allium cepa L.), growing in open felds of the Santa Catarina State in Brazil, displayed symptoms similar to those caused by Pantoea ananatis. Symptoms included water-soaked lesions, bleached leaves and rotten bulbs. Infected scales, usually the internal ones near the centre, were light to dark brown in colour and softened. To isolate the causal agent, symptomatic samples from leaf and bulb tissues were surface-disinfested in 70% ethanol for 30 s, rinsed 3 times in sterilized water, and then ground in sterile water and streaked on nutrient agar plates incubated for 36 h at 27 °C. The yellowpigmented, raised, irregular border, and translucent colonies were selected as candidates. To confrm the identity of the isolated bacteria, the DNA of the isolates, EITB35 and EITB48, were PCR amplifed with P. ananatis-specifc primers: PANA_1080 61F/1009R (Asselin et al. 2016). Both isolates could be detected by PANA_1080 61F/1009R primers. Furthermore, DNA gyrase subunit B (gyrB) was PCR amplifed with the primers gyrB 1480F/2242R (Bonasera et al. 2014). The gyrB sequences of isolates were deposited in GenBank with accession numbers OK247424 and OK247425. Phylogenetic analysis based on Bayesian inference was conducted and confrmed the BLAST results. The gyrB sequences of both isolates clustered, with high posterior probability values, in the clade containing the type strain of P. ananatis, LMG 2665, along with other isolates of this species, indicating that they belong to P. ananatis. Additionally, pathogenicity tests were conducted on leaves and bulbs by injection with bacterial suspension of 108 CFU ml&#8722;1, according to Carr et al. (2013). After 7 to 21 days, symptoms on leaves and bulbs, respectively, were developed and resembled those of natural infections. The bacterium was then re-isolated from symptomatic bulbs and leaves and confrmed as P. ananatis using morphological characteristics on nutrient agar medium. Pantoea ananatis has been identifed to infect onion in other onion-growing regions of the world, including EUA, Korea and Taiwan. To our knowledge, this is the frst ofcial report of P. ananatis infecting onion in Brazil. The impact of P. ananatis on onion production  is unknown, but the establishment of efective management strategies will be needed to prevent potential economic loss in the future.
Palavras-Chave: | Allium cepa; Bacterial disease; Postharvest pathology.
Categoria do assunto: | F Plantas e Produtos de Origem Vegetal
URL: | http://intranetdoc.epagri.sc.gov.br/producao_tecnico_cientifica/DOC_50444.pdf
Registro original: | Epagri-Sede (Epagri-Sede)
Exemplares: | Epagri-Sede - (106522-1) - UPC - AP - DD -  -  -  - DIS